Extrapolation means you have frame 1, and sometime in the future you'll get a frame 2. But until then, take the training data and the current frame and "guess" what the next few frames will be.
Interpolation requires you to have the final state between the added frames, extrapolation means you don't yet know what the final state will be but you'll keep drawing until you get there.
You shouldn't get additional latency from generating, assuming it's not slowing down the traditional render generation pipeline.
